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Rate theory for correlated processes: Double-jumps in adatom diffusion

Joachim Jacobsen·Karsten W. Jacobsen·James P. Sethna
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Abstract

We study the rate of activated motion over multiple barriers, in particular the correlated double-jump of an adatom diffusing on a missing-row reconstructed Platinum (110) surface. We develop a Transition Path Theory, showing that the activation energy is given by the minimum-energy trajectory which succeeds in the double-jump. We explicitly calculate this trajectory within an effective-medium molecular dynamics simulation. A cusp in the acceptance region leads to a sqrt{T} prefactor for the activated rate of double-jumps. Theory and numerical results agree.

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Joachim Jacobsen, Karsten W. Jacobsen, James P. Sethna. 1997-07-04. Rate theory for correlated processes: Double-jumps in adatom diffusion. https://doi.org/10.1103/physrevlett.79.2843

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